Consumer electronics continue to shrink in physical size while manufacturers of consumer devices continue to demand improved performance, additional functionality, lower power, and more design flexibility. As examples, manufacturers are today making cell phones that are no bigger than a cigarette lighter, smart cards that contain kilobytes of information and advanced security features, and hand held devices which are communicating and processing at rates that were only possible on workstations a short decade ago. In order to accommodate these smaller and higher performance devices, the semiconductor industry has continued to produce integrated circuits with increasingly smaller feature sizes (0.5 microns or less), radically new packaging techniques and materials, and with much faster frequencies of operation (50 MHz or above). In addition, these products are being made using processes that are much more complex than that used for microcontroller (MCU) applications just years ago. Due to the increasing complexity of the integrated circuits (ICs), increasing process complexity, and the ever increasing capacity of memory required within consumer electronic devices, consumer integrated circuits have now progressed to a point where it is very difficult to guarantee 10 years or more of reliable data retention. Such long-term and reliable retention within the embedded non-volatile memory (NVM) of a consumer product is crucial, else the product will generally not obtain competitive market acceptance.
In the past, 10 years or more of NVM data retention was guaranteed by manufacturing embedded consumer devices that were much larger and more conservative than the most aggressive technology available. However, in order to meet the performance, power, size, and flexibility needs of the current market, it is now necessary to use much more aggressive circuit designs and IC. When using more aggressive designs and processes, the 10 year NVM data retention minimum required by the consumer market is much more difficult to consistently achieve. In some cases, yields have fallen, costs have increased, and time to market has suffered. Therefore, a need exists in the industry for a method of guaranteeing error free operation of consumer embedded memory devices for periods of 10 years or longer while simultaneously using more aggressive IC processing, more complex materials and packaging, along with more advanced device structures. In addition, this new method should ensure that the overhead of obtaining such a solution does not significantly impact a size of the IC device or a cost of manufacturing the device.